Ronnie charged his computers a flat fee of $25 to fix computers. Then he charged $20 for each hour that he spent fixing the computer. If Ronnie made $175 off of his first computer, how many hours did he spend working

7.5

Step-by-step explanation:

Ronnie charges $25 plus $20 per hour. This means that he made the following depending on how many hours he spent on it:

Hours Dollars

0 25 = 25 + 0 (20) = 25

1 25+20 = 25 + 1 (20) = 45

2 25+20+20 = 25 + 2 (20) = 65

3 25+20+20+20 = 25 + 3 (20) = 85

4 25+20+20+20+20 = 25 + 4 (20) = 105

5 25+20+20+20+20+20 = 25 + 5 (20) = 125

...

n 25+n (20) = 175

To find how many hours he worked for $175 we solve the equation using inverse operations:

25+n (20) = 175

25-25+n (20) = 175-25

n (20) = 150

n = 7.5 hours